One of the first, and most important, decisions a rice producer makes each year is which variety to grow in each production field. The first decision is whether to grow a long-grain or medium-grain type variety. Twenty-five years ago Louisiana was predominantly a medium-grain producing state. In the decade of the 1980s, we planted approximately 65 percent of our acreage in medium-grain varieties, with the reminder seeded to long-grain types. That has changed dramatically since then. In 2008, Louisiana planted over 95 percent of our acreage in long-grain types, with the remainder devoted to medium grains. These changes occurred because of the market, as well as the release of more yield-competitive long-grain varieties. For the 2009 season, however, there is more interest in medium grains primarily because of a fairly good price for contracted medium-grain rice.

Louisiana farmers have three choices of medium-grain varieties: Bengal, Jupiter and Neptune. Bengal is an old variety that was the medium-grain standard for many years. Jupiter (released in 2005) and Neptune (released in 2008) are improved varieties, especially in yield potential. Both of the newer varieties also have a much better disease package compared with Bengal and will probably replace the acreage seeded to Bengal in the future. While Neptune has slightly lower yield potential than Jupiter, it has a bolder grain and better head rice milling yields on average. Typically, medium-grain varieties are not as consistent as long grains in the production of a ratoon (second) crop. Neptune appears to be the exception to this and has consistently shown second crop grain yields comparable with the best long grains.

If a long grain is to be planted, one must first decide whether to grow a conventional line or a Clearfield variety. Planting a Clearfield variety allows the use of NewPath (and Beyond) herbicide, which helps control weedy red rice in a commercial rice field. If planting a conventional long grain, the predominant varieties are Cocodrie, Cheniere, Trenasse and Catahoula. All of these varieties have very good (and comparable) yield potential. Trenasse is the earliest of the four and also the tallest and most susceptible to lodging. Cocodrie, Cheniere and Catahoula all exhibit semidwarf erect plant types and display excellent resistance to lodging.

While Catahoula and Cheniere are susceptible to sheath blight disease, they are both somewhat more resistant than Cocodrie. Cocodrie is also the most susceptible of the three to straighthead disorder, and Cheniere is the most resistant, with Catahoula rating between these two. Catahoula has the highest level of resistance to blast disease and typically has the highest whole-grain milling yields of the three varieties. All of these varieties have very good second cropping characteristics, which is an important consideration in southwest Louisiana.

Four choices of a Clearfield variety are available in 2009: CL131, CL151, CL161 and CL171. While all of these long-grain varieties have good yield potential, CL151, the newest of the four, has consistently displayed a significant yield advantage over the others. Based on disease screening research conducted by Dr. Don Groth, CL151 appears to be somewhat more tolerant to sheath blight disease, especially when compared with CL131 and CL161. CL131 and CL151 are also more susceptible to straighthead disorder. All of these varieties are susceptible to blast disease. While all four Clearfield varieties have consistently shown good head rice milling yields, CL151 tends to display more chalky kernels than the other three.

As rice growers make their decisions, they need to be aware that all rice varieties – including the new ones – have strengths and weaknesses.

DERMACOR X-100

Louisiana has been granted a Section 18 exemption for the use of Dermacor X-100 as a rice seed treatment for the control of the rice water weevil, the most destructive early season insect pest in rice production in the state. Seed treated with Dermacor X-100 will be available only from approved seed treatment facilities and is only approved for use in dry-seeded rice. This DuPont product was also granted a Section 18 registration in 2008, which provided an opportunity to evaluate the compound in commercial fields. Dr. Natalie Hummel worked with county agents and producers to evaluate the performance of the product in several commercial fields last year. The results of this monitoring program confirmed what Dr. Mike Stout had observed in several years of research with the product – Dermacor X-100 is an excellent product for controlling the rice water weevil.